package com.atguigu.day05;

import com.atguigu.bean.WaterSensor;
import org.apache.flink.api.common.eventtime.*;
import org.apache.flink.api.common.functions.MapFunction;
import org.apache.flink.api.java.tuple.Tuple;
import org.apache.flink.streaming.api.datastream.DataStreamSource;
import org.apache.flink.streaming.api.datastream.KeyedStream;
import org.apache.flink.streaming.api.datastream.SingleOutputStreamOperator;
import org.apache.flink.streaming.api.datastream.WindowedStream;
import org.apache.flink.streaming.api.environment.StreamExecutionEnvironment;
import org.apache.flink.streaming.api.functions.windowing.ProcessWindowFunction;
import org.apache.flink.streaming.api.windowing.assigners.TumblingEventTimeWindows;
import org.apache.flink.streaming.api.windowing.time.Time;
import org.apache.flink.streaming.api.windowing.windows.TimeWindow;
import org.apache.flink.util.Collector;

import java.time.Duration;

import static org.apache.flink.util.Preconditions.checkArgument;
import static org.apache.flink.util.Preconditions.checkNotNull;

public class Flink13_EventTime_WaterMark_Customer {
    public static void main(String[] args) throws Exception {
        //1.获取流的执行环境
        StreamExecutionEnvironment env = StreamExecutionEnvironment.getExecutionEnvironment();
        env.setParallelism(1);

        //手动设置WaterMark生成的周期时间
        env.getConfig().setAutoWatermarkInterval(1000);

        //2.从端口读取数据
        DataStreamSource<String> streamSource = env.socketTextStream("localhost", 9999);
//        DataStreamSource<String> streamSource = env.readTextFile("input/sensor.txt");

        //3.将数据转为WaterSensor
        SingleOutputStreamOperator<WaterSensor> waterSensorStream = streamSource.map(new MapFunction<String, WaterSensor>() {
            @Override
            public WaterSensor map(String value) throws Exception {
                String[] split = value.split(",");
                return new WaterSensor(split[0], Long.parseLong(split[1]), Integer.parseInt(split[2]));
            }
        });

        //TODO 4.指定WaterMark以及事件时间
        SingleOutputStreamOperator<WaterSensor> waterSensorSingleOutputStreamOperator = waterSensorStream.assignTimestampsAndWatermarks(WatermarkStrategy
                //自定义生产WaterMark
                .forGenerator(new WatermarkGeneratorSupplier<WaterSensor>() {
                    @Override
                    public WatermarkGenerator<WaterSensor> createWatermarkGenerator(Context context) {
                        return new MyWaterMark(Duration.ofSeconds(3));
                    }
                })
                .withTimestampAssigner(new SerializableTimestampAssigner<WaterSensor>() {
                    @Override
                    public long extractTimestamp(WaterSensor element, long recordTimestamp) {
                        return element.getTs() * 1000;
                    }
                })
        );

        KeyedStream<WaterSensor, Tuple> keyedStream = waterSensorSingleOutputStreamOperator.keyBy("id");

        //开启基于事件时间的滚动窗口
        WindowedStream<WaterSensor, Tuple, TimeWindow> window = keyedStream.window(TumblingEventTimeWindows.of(Time.seconds(5)));


        SingleOutputStreamOperator<String> process = window.process(new ProcessWindowFunction<WaterSensor, String, Tuple, TimeWindow>() {
            @Override
            public void process(Tuple tuple, Context context, Iterable<WaterSensor> elements, Collector<String> out) throws Exception {
                String msg =
                        "窗口: [" + context.window().getStart() / 1000 + "," + context.window().getEnd() / 1000 + ") 一共有 "
                                + elements.spliterator().estimateSize() + "条数据 ";
                out.collect(msg);
            }
        });

        process.print();
        env.execute();

    }
    public static class MyWaterMark implements WatermarkGenerator<WaterSensor>{

        //到目前为止遇到的最大时间戳
        private long maxTimestamp;

        /** 该水印生成器所假定的最大无序性. */
        private long outOfOrdernessMillis;

        public MyWaterMark(Duration maxOutOfOrderness) {

            this.outOfOrdernessMillis = maxOutOfOrderness.toMillis();

            // 使我们的最低水位为Long.MIN_VALUE
            this.maxTimestamp = Long.MIN_VALUE + outOfOrdernessMillis + 1;
//            this.maxTimestamp = Long.MIN_VALUE ;
        }
        @Override
        public void onEvent(WaterSensor event, long eventTimestamp, WatermarkOutput output) {
//            System.out.println("eventTimestamp:"+eventTimestamp);
            maxTimestamp = Math.max(maxTimestamp, eventTimestamp);
//            System.out.println("WaterMark:"+(maxTimestamp-outOfOrdernessMillis-1));
            //间歇性生成WaterMark
//            output.emitWatermark(new Watermark(maxTimestamp-outOfOrdernessMillis-1));
        }

        @Override
        public void onPeriodicEmit(WatermarkOutput output) {
            System.out.println("WaterMark:"+(maxTimestamp-outOfOrdernessMillis-1));
            //周期性生成WaterMark
            output.emitWatermark(new Watermark(maxTimestamp-outOfOrdernessMillis-1));
        }
    }
}
